What the question is asking for is a 3-dimensional shape that has a lot of surface area and only a little volume. The first thing I thought of was a geometric figure called Gabriel's Horn. A quick search on Wikipedia will explain better than I can, but basically it has infinite surface area but finite volume. You probably couldn't test the shape in any experiment, though, since it's only theoretical and can't exist in real life.
Let me know if I can explain anything in a clearer way!
The hair is made up of 95% keratin, a fibrous, helicoidal protein (shaped like a helix) that forms part of the skin and all its appendages (body hair, nails, etc.). Keratin is synthesized by keratinocytes and is insoluble in water, thus ensuring impermeability and protection for the hair.
